The invention is directed to improvements to modular dwellings and more specifically is directed to improvements to such dwellings that include roof panels and a truss system for a roof of a dwelling in which horizontal truss members support one set of roof panels from an upper region of the truss system and support another set of roof panels from a lower region of the truss system. The sets of roof panels extend outwardly in opposite directions from the truss members supported by opposite walls of the dwelling. The truss members are supported only at each end thereby forming a large inner area of the dwelling beneath the roof panels and truss system free of internal support members. The truss members may include inner windows permitting natural light to enter the dwelling from outside.